Printed circuit boards (PCBs) are structures having a rigid, non-conductive substrate layer or a laminate of multiple substrate layers and carefully designed conductive pathways for routing electric/electronic signals and electric power to a circuit assembly that is typically mounted on the PCB surface. The circuit assembly may include various electrical and electronic components and one or more devices. The conductive pathways may be located along the surface of the substrate or may be embedded at layers within a multi-layer substrate. The easy movement of electronic signals and electric power helps the electronic devices to operate without interruption.
The embedded or surface located conductive pathways may be formed as copper foil, copper wires or copper sheets, however may comprise any conductive material.
A PCB typically includes pads on the top and/or bottom surfaces for use as contacts to other components or other printed circuit boards.
Traditionally pins are attached to contact pads on the top or bottom surface of the PCB. Vias then anchor the outer layer pads to internal layer metal structures to provide improved mechanical robustness and electrical conductivity.
Forming pads or contacts along the perimeter of the top or bottom Areal Main Faces (AMFs) of a PCB can limit the number and density of the contacts. In some cases, PCBs have a plated Peripheral End Face (PEF) to facilitate direct soldering to other circuit boards. However, when it is required to have one PCB mounted to another PCB, pins are commonly used in the circuit assembly.
The attaching of contact pins to the top or bottom surfaces of a PCB consumes area on many or all layers of the board. Existing methods of such peripheral end face attachment often use pins or connectors, which add cost and add electrical and thermal resistance.